Woodwool is normally used to provide a large surface area for the evaporation of water in an evaporative type cooler, and the most successful woodwool pad arrangement used at the present time has fibres of woodwool retained together by a wire cage. Other absorptive materials may be used in lieu of woodwool. This functions very satisfactorily, but one of the problems is that the woodwool gradually sags, or reduces its height, and with previously proposed water distribution means, a gap sometimes develops between the distributor and the upper edge of the woodwool pad, and this functions as a "short circuit" allowing water droplets to be picked up by the stream of air which would otherwise pass entirely through the pad.